Recent developments in the semiconductor integrated circuit (IC) technology include microelectromechanical system (MEMS) devices. MEMS devices include mechanical and electrical features formed by one or more semiconductor manufacturing processes. Examples of MEMS devices include micro-sensors, which convert mechanical signals into electrical signals; micro-actuators, which convert electrical signals into mechanical signals; and motion sensors, which are commonly found in automobiles (e.g., in airbag deployment systems). For many applications, MEMS devices are electrically connected to integrated circuits (ICs) to form complete MEMS systems.